Starting build modifier from one end
You need to sort the vertices:

In Edit mode, select the vertex that you want to choose as the first one, then ShiftS &gt; Cursor To Selected.



Select all, go in the Mesh menu &gt; Sort Elements &gt; Cursor Distance.



In the Operator box, click on Face. Now it should work. If you want to check the vertices numbers, go in the Preferences &gt; Interface &gt; Display &gt; enable Developer Extras. Then in the 3D view &gt; Viewport Overlays &gt; Developer, enable Indices.